iOS 对字符串进行ASCII码排序

NSString *signValue = [NSString stringWithFormat:@"%@%@", valueJson, [Utility getCurrentTimes]];

        NSMutableString * getSignString = [NSMutableString string];

        NSMutableArray * mutaArray = [NSMutableArray array];

        for (int i = 0; i < [signValue length]; i ++) {

            [mutaArray addObject:[signValue substringWithRange:NSMakeRange(i, 1)]];

        }

        NSStringCompareOptions comparisonOptions = NSCaseInsensitiveSearch|NSNumericSearch|

        NSWidthInsensitiveSearch|NSForcedOrderingSearch;

        NSComparator sort = ^(NSString *obj1,NSString *obj2){

            NSRange range = NSMakeRange(0,obj1.length);

            return [obj1 compare:obj2 options:comparisonOptions range:range];

        };

        NSArray *resultArray2 = [mutaArray sortedArrayUsingComparator:sort];

        for (NSString * oldString in resultArray2) {

            [getSignString appendString:oldString];

        }

//signValue为输入字符串， getSignString为最后得到字符串

iOS 对字符串进行ASCII码排序

原文：https://www.cnblogs.com/allenwuhen/p/9680476.html